Hemin

noun

1. The reddish-brown crystalline chloride of heme, C₃₄H₃₂N₄O₄FeCl, produced when hemoglobin reacts with glacial acetic acid and sodium chloride in a laboratory test for the presence of blood.
2. A crystalline substance which may be obtained from hematin on treating it with salt and glacial acetic acid. Its formula is C₃₄H₃₃N₄O₄FeCl. The crystals are quite characteristic in appearance, and their formation has for many years represented one of the most important tests for blood-coloring matter. See <internalXref urlencoded="Teichmann%27s">Teichmann's</internalXref> <internalXref urlencoded="crystals">crystals</internalXref>.
3. A substance, in the form of reddish brown, microscopic, prismatic crystals, formed from dried blood by the action of strong acetic acid and common salt; -- called also <ex>Teichmann's</ex> crystals. Chemically, it is a hydrochloride of hematin.
4. a <xref>reddish</xref> <xref>brown</xref> substance produced in a <xref>laboratory</xref> <xref>test</xref> for the presence of <xref>blood</xref> by reaction with <xref>glacial acetic acid</xref> and <xref>sodium chloride</xref>
5. a reddish-brown chloride of heme; produced from hemoglobin in laboratory tests for the presence of blood